The CPOs are fine with bending, because it's a lot like the vinyl people here use from Happs. I was going to go without plexi on the surface, but I was having a lot of problems keeping it from getting small bubbles here and there, so I just opted for plexi and it's been perfect since. If you were to use a spray glue underneath it would help keep it from bubbling, but the edges of the art should be protected with something (or tucked underneath the panel) or else they'll eventually fray.
The product Mamemarquee puts out though is awesome quality! I would definitely pay what it takes for their service so you can enjoy the results and save the aggravation.